1. Field
The present disclosure generally relates to optical networks. More specifically, the present disclosure relates to an optical network that includes a node with a circuit switch that is configured to implement a predefined network topology.
2. Related Art
Photonics technology provides high-bandwidth densities and low energy-per-bit compared to conventional electronic interconnects. However, a significant fraction of the power in a photonic interconnect is typically static because of the constant laser source and statically tuned micro-rings. If some of the optical links in an optical interconnect are not used by the communication traffic, the bandwidth is under-utilized and energy is wasted. In particular, an unused optical link burns nearly as much power as a used one.
For example, in a system with a cluster of nodes interconnected using a point-to-point (P2P) network, the P2P network gives high levels of performance for high-radix traffic. However, with low-radix traffic patterns a large fraction of the optical links on each node is not used.
The source of the low-radix traffic depends on the how the system is used. In a first use case, the system can be used to run a single large parallel application, and the application may exhibit low-radix communication. However, not all of the nodes in the system may communicate with each other, so there may be unused optical links. Alternatively, in a second use case, the system can be multi-programmed by partitioning it into multiple virtual machines (VMs). Because the communication between the VMs may be minimal or non-existent, there may be idle inter—VM optical links. In both of these cases, optical bandwidth and power are wasted because the underlying network topology is ill-suited to the target application and system configuration.
Hence, what is needed is a network that does not suffer from the above-described problems.